RmvBfrFlght
Well-Known Member
- Joined
- Sep 28, 2007
OK, the question is: why does the line pressure fall off as the RPM increase. Seems to start at around 2400 RPM.
This is a 200-4R, modified/built, has a stock pan with the CK spacer and the 700R4 filter, .555 main boost and a .284 low/rev boost valve. Trans-go kit with the proper TV line up. Line pressure at 1100 RPM is as follows:
Note that I used the ECM to increase the idle speed, so the idle position is with the TV connected and the throttle body on the idle stop screw. The min is TV disconnected, max with it pulled all the way out.
However, at a higher RPM that max pressure isn't reached. Here is a graph of a data log showing this:
Note how the line pressure starts to fall off at the RPM climbs to the 2400 RPM range. The trans downshifts on the 100% TPS into 1/2 with the pressure falling even further. Why?
The gear selection stick was in D3 the whole time. I'm rather stumped as I'm no expert on transmissions.
RemoveBeforeFlight
This is a 200-4R, modified/built, has a stock pan with the CK spacer and the 700R4 filter, .555 main boost and a .284 low/rev boost valve. Trans-go kit with the proper TV line up. Line pressure at 1100 RPM is as follows:
Note that I used the ECM to increase the idle speed, so the idle position is with the TV connected and the throttle body on the idle stop screw. The min is TV disconnected, max with it pulled all the way out.
Code:
Idle Min Max
P 89 80 220 psi
R 140 125 210
N 89 80 215
4 89 80 200
3 89 80 200
2 195 190 195
1 195 190 180
However, at a higher RPM that max pressure isn't reached. Here is a graph of a data log showing this:
Note how the line pressure starts to fall off at the RPM climbs to the 2400 RPM range. The trans downshifts on the 100% TPS into 1/2 with the pressure falling even further. Why?
The gear selection stick was in D3 the whole time. I'm rather stumped as I'm no expert on transmissions.
RemoveBeforeFlight